The pilot episode, also known as "Northwest Passage", of the mystery television series Twin Peaks premiered on the ABC Network on Sunday, April 8, 1990. It was written by series creators Mark Frost and David Lynch, and directed by Lynch. The pilot follows the characters of Dale Cooper and Harry S. Truman as they investigate the death of popular high school student Laura Palmer; Cooper believes the murder has connections to a murder case that occurred a year earlier. In addition to setting the tone for the show, the episode sets up several character and story arcs and marked the appearance of several recurring characters. The episode received a strong Nielsen household rating compared to other season one episodes, and was well received by fans and critics alike. The original title for the series was Northwest Passage, but this was later changed.